This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Cardiomyopathy is an important complication of chronic kidney disease especially in children with steroid resistant nephrotic syndrome. The incidence may be higher in those with primary or idiopathic focal segmental glomerulosclerosis (FSGS). This study will determine the prevalence of abnormalities in cardiac function and the course of any cardiomyopathy in children with FSGS compared to other forms of steroid resistant nephrotic syndrome and determine whether it is impacted by specific genetic subtypes of primary FSGS.